1. Field of the Invention
The present invention relates to an apparatus for filtering particles from gaseous fumes, and more particularly, but not by way of limitation, to an improved air cleaner assembly for capturing and filtering gaseous fumes at their source.
2. Discussion of Related Art
In the past, it was common to use large exhaust hoods or fans to remove indoor industrial pollutants, such as welding smoke, grinding dust and other gaseous fumes. In recent years, however, it has become more common to remove these pollutants with localized exhaust fans or blowers provided with maneuverable capture arms or with fixed and portable air cleaners.
Focusing on the latter, air cleaners typically include a housing, a blower and an air filter. The blower draws the fumes into the housing and through the filter where the suspended particles are collected. The blower then exhausts the filtered air from the housing. Often a receptacle or dust tray is provided in which heavier particles, such as sparks, are collected. It is also common to provide an air cleaner with a backflushing system with which to clean the filter after an extended period of use. The particles removed from the filter by the backflushing system are collected in the dust tray and subsequently disposed of along with the heavier particles previously collected.
While several prior art air cleaning devices have met with some success, problems have nevertheless been encountered with the use of such devices. For example, as a result of the configuration and positioning of the dust trays, heavier particles are not effectively collected in the dust tray, thereby resulting in such particles being collected in the filter and in turn shortening the life of the filter. Further, backflushing systems employed in prior art devices do not efficiently flush the particles from the filter; that is, typical backflushing systems flush only a small portion of the filter. An additional problem with prior art devices is that the particles that are flushed from the filter are sucked back into the filter once the filtering process is resumed, thus requiring that the dust trays be removed and emptied after each cleaning.
Therefore, it has long been recognized that a need exists for an improved air cleaner assembly which operates more efficiently and which overcomes the deficiencies of prior art air cleaners. It is to such an improved air cleaner assembly that the present invention is directed.